CORNEAL OEDEMA

On the basis of Wollensak et al. [1] demonstrating that riboflavin/UVA cross-linked pig corneas placed in a humidity chamber swell less than untreated corneas, cross-linking was proposed as a therapeutic option for the treatment of corneal oedema. In practice however the standard riboflavin/UVA cross-linking protocol appears to produce only short term improvements in pain, irritation and discomfort, and sometimes (but not always) results in a reduction in corneal thickness [2,3]. Modified riboflavin/UVA cross-linking techniques in which swollen corneas are dehydrated to a normal thickness prior to treatment have produced favourable results, with distinct reductions in corneal thickness and patient discomfort being reported immediately post surgery [4] and up to 8 months post treatment [5].

Although CXL may not prevent the need for corneal transplantation in conditions involving corneal oedema, it should be noted that the therapy has the potential to significantly improve patient’s visual comfort and extend the time interval for an upcoming corneal transplantation.